Review request for HKJ [Rechargeable Batteries]

Just remembered the cells the Kreosan Ukrainian guys played with in this thread's video: Testing 18650 Safety - Russian Style

I believe their OEM is Heter, meant for the electric vehicle market. I wonder if there's room for a review of them, they're technically a mid-power sub-2800mAh cell (EAIEP 2pcs “26F” sale link).

Thanks.

The meter only measures, it do not do any PWM or other regulation.

Hello! :-))

How are your battery queues doing, Henrik? Is there place for some 2800mAh max cell?

Lanzhd 18650 Store has some sort of rewrapped power cell in purple wrap, likely manufactured by BAK Power. Also, a realistically rated USB micro-B rechargeable 650mAh 16340 li-ion cell.

There's a small AliExpress sale in a few hours. I am not particularly interested in the 16340, but others may. In the meantime I may look for some co-funding for the other cell (because ;-) I'm rich). Anyone here?

It is winding down, lately I have published fewer battery reviews due to that.

?

To send you some of my previously mentioned cells, that is. Just looking for some shared interest.

I am interested in that.

Anyone know who makes the manker 2600mah flat top battery? I know its just a rewrap but just curious as they retail for 18 dollars

Hello!

Quick question aimed at Henrik, did you receive the VariCore 32700 LiFePO4 6500mAh (Gray) cells from AliExpress' store #1874160 (https://entemple.aliexpress.com/store/1874160)?

Oh! Wellp, nevermind really. Found this Shop2097037 with slightly better pricing, interesting cells and cell packs.

They're selling this weird LiitoKala branded li-ion 7200mAh :???: 26800 cells with tabs, guess that is some electric vehicle market product (5C discharge rating). And I must also say, without a doubt, that 7200mAh in a 26800 is high energy density, beating PLB 5500mAh at least on paper.

Henrink, did you ever tested some electronic load like the following? (guess the answer is not yet)

https://www.aliexpress.com/item/32725711985.html

Had a different, more display fancy electronic load in my wishlist but people were reporting failure to disconnect load after voltage cut-off in it. This one has good reports, guess I would only need a battery holder to complement with it.

Found a cheaper sale for the 26800s in small quantities, without tabs and less overrated; just in case Henrik would want to test such weird cells: https://www.aliexpress.com/item/4000218361115.html

Does anyone knows what OEM could be manufacturing such spring rolls?

Sun, 10/20/2019 - 08:49; Sun, 10/20/2019 - 09:13

I got and tested the Varicore batteries some time ago.

I started on in once, but it died on me. The problem is when they use a single mosfet transistor, standard mosfets are not good at analog regulation and cannot handle anything like the rated power when doing that.

That cell is a problem, it will not fit in my battery holders, 70mm long is about maximum I can test.

I guess it died once you tested it at some power level within theoretical specifications, do you remember how much was that?

Found a review of it: Queen Battery QB26800 6800mAh 20A - the big guy! @ Thunderheart Reviews

Nice battery holder, doesn't it? :-D

It was close to maximum rated power.

It is similar to the ones I used before.

I bought some aaa batteries from ebay. The picture showed contour batteries. I think this is a good company which closed down or something…when they arrived they were Digimax. I discharged then charged them at 200mA in an Accupower IQ328 and two of them kept fluctuating between 1.41v and 1.42v. I ended up stopping the charge after 5 and a half hours! I know the current should be at least 0.3C but I wasn’t expecting this from brand new batteries. I always select the lowest current for new cells and when condition cells.

4 AAA batteries

Today i tested the “7000mAh” LiFePo4 cells after they are used for more than 10 months in the solar powered light. https://nl.aliexpress.com/item/32878468860.html?spm=a2g0z.10010108.1000013.5.3d9e7580Cyry4Y&pvid=c5572a18-c89d-440b-a640-9a2bed6460af&gps-id=pcDetailBottomMoreThisSeller&scm=1007.13339.90158.0&scm-url=1007.13339.90158.0&scm_id=1007.13339.90158.0
According to the HTRC B6V6 balance charger the discharge capacity of the 2S battery pack is still 6459mAh (about the same as in the first test, almost one year ago).

The balance board does not balance the cells, but that is no problem because charging and balancing the battery pack after taking it off the wall took only 4 minutes and 2 seconds
(The cells were charged and balanced before capacity test.)
If there would have been a large difference between the two cells, the charge/balancing time would have taken much longer than 4 minutes.

These cells are much better than the Original lead-acid battery that became useless after about one year.
A new 6V/4A lead acid battery is also more expensive than these cells + the protection board.
The LiFePo4 cells are still like new, it looks like they will last many years in that solar powered light.

I like the tests of new cells, but i am also interested in re-tests after they have been used in “real life conditions”.
I know it is very difficult to do that, but in this case i will continue testing these cells once a year

In my experience balance boards are designed to start resistor draining the cells at some overvoltage (overcharge) point. This, in my opinion, is a simple but effectively useless approach as overvoltage hastens cell damage (you want your cells to live long, not to die soon).

To keep cells in balance manually I would install voltmeters and pushbutton enabled bleeding resistors at each battery stage.

Hello HKJ,

Have you planned to test the upgraded version of the formerly reviewed Kentli or the AAA version?

https://www.aliexpress.com/item/32798542354.html

https://www.aliexpress.com/item/32798806801.html

Not really, but now you asked I decided to order them.

I saw some NCR18650ga on aliexpress I’m curious about for ~$2/ea. Do you have any opinions about them?

https://www.aliexpress.com/item/33026381615.html
https://www.aliexpress.com/item/4000291832886.html
https://www.aliexpress.com/item/4000291932072.html
https://www.aliexpress.com/item/4000278525687.html

Not really, neither the wrapper or button top is original, but I do not know if the battery is original (Probably not).

Thanks, I’ll save my money